Predictive factors for secondary alveolar bone graft failure in patients with cleft alveolus

Prediction of Alveolar Cleft Reconstruction Outcomes: From the Perspective of Systemic Inflammatory Status and Local Structural Characteristics

INTRODUCTION

To promote alveolar cleft reconstruction outcomes, it is crucial to identify the factors that may influence postoperative bone formation. Both local structural characteristics and systemic inflammatory status are closely related to bone formation, requiring comprehensive investigation. This study aimed to investigate the impact of these potential influencing factors on the bone formation percentage (BFP) of alveolar bone grafting.

MATERIALS AND METHODS

A retrospective study was conducted on patients who underwent alveolar bone grafting by the same surgeon between 2017 and 2023. Demographic data, preoperative blood test results, and various local structural characteristics were investigated as independent variables. The BFP was considered as a dependent variable. Correlation and multiple linear regression analyses were performed to determine the key factors influencing BFP. The ROC curve analysis was utilized to evaluate the predictive efficacy.

RESULTS

Fifty-five patients met the inclusion criteria. The mean BFP was 39.75%±19.68%. The initial bone bridge was an independent positive influencing factor of BFP, whereas the preoperative lymphocyte percentage (L%) was negative. According to ROC curve analysis, a value of L% equal to 34.9% was the optimal cutoff point for whether the BFP was >39.75%. Other parameters were nonsignificantly correlated with BFP.

CONCLUSION

The presence of the bone bridge and a lower value of L% may indicate a better postoperative bone formation outcome. These findings can help surgeons identify patients who are more likely to achieve favorable bone grafting results based on readily available CT images and preoperative blood tests.

Alveolar Bone Graft Supplemented With Stromal Vascular Fraction in Patients With Permanent Dentition: A Randomized Study

OBJECTIVE

To evaluate bone development in patients with alveolar clefts and permanent dentition treated with alveolar bone graft supplemented with stromal vascular fraction (SVF).

DESIGN

Clinical, prospective, randomized.

LOCATION

Single tertiary care institution.

PATIENTS

Eighteen participants with unilateral alveolar cleft and permanent dentition were included. Patients with other comorbidities were excluded.

INTERVENTION

The control group underwent alveolar bone grafting (ABG) using iliac crest bone, while the experimental group underwent the same treatment, supplemented with SVF. Adipose tissue was collected by abdominal liposuction, and the SVF was processed using mechanical methods (decantation, microfragmentation, and filtration).

MAIN OUTCOME MEASUREMENT

Bone formation and bone graft integration rate in alveolar cleft at 6 months postsurgery using 3-dimensional tomographic methods and density measurements.

RESULTS

The amount of bone graft correlated with an improvement in the relationship between the cleft and noncleft sides (R = 0.78, P < .001) and an improvement in alveolar cleft density (R = 0.69, P = .005), but did not correlate with the graft integration rate. The experimental group showed larger cleft sizes (0.83 × 1.74 cm3, P = .021) and older patients (17.35 × 27.6 years, P = .002), and did not differ in terms of bone development variables when compared to the control group.

CONCLUSION

ABG supplemented with SVF showed statistically similar bone development results, but with a better trend than conventional ABG. Additionally, the studied groups had asymmetric pre-existing characteristics, with greater severity in the experimental group. A larger study will be necessary to mitigate preoperative characteristic differences and to more accurately compare the results between the methods.

Outcomes of Xenograft with Platelet-rich Fibrin versus Autogenous Bone in Alveolar Cleft Grafting

Background

The use of a suitable graft material helps with sufficient osseointegration. The aim of this study was to compare the clinical and radiographic outcomes of two types of alveolar bone graft materials, xenografts with platelet-rich fibrin (PRF) and autogenous grafts, in patients with alveolar clefts.

Methods

Thirty-six patients with alveolar clefts were enrolled in this study. Those patients were randomly divided into two groups: group A, where the autogenous iliac bone graft was used to fill the alveolar defect, and group B, where the xenograft with PRF was used to fill the alveolar defect. After 6 months of grafting, patients were assessed in terms of pain, duration of hospital stay, and donor site morbidity associated with iliac crest harvesting, while bone formation was evaluated radiographically using cone beam computed tomography.

Results

The results showed no statistical differences as regards baseline and perioperative data. Operative duration was significantly lower among xenograft with PRF patients. Both groups had comparable postoperative success scores, and total failure was reported in a total of three patients (one patient in group A and two patients in group B).

Conclusions

With no potential donor site morbidities, xenograft with PRF is an equivalent bone transplant replacement to the autologous iliac bone graft. Additionally, it is associated with a significant success rate, and a significant decrease in operative time and hospital stay. Many future studies are warranted to draw firm conclusions.

Evaluation of Secondary Alveolar Bone Grafting for Unilateral Complete Cleft Alveolus: A Retrospective Cone Beam Computed Tomography-Based Study

Background: In patients with cleft lip and palate (CLP), secondary alveolar bone grafting (SABG) with particulate cancellous bone marrow (PCBM) is recommended. Objective: To compare bone graft outcomes in patients with unilateral CLP, when SABG is completed before or after canine tooth eruption (ACE or BCE), as measured by cone beam computed tomography (CBCT). Methods: Patients were allocated into two cohorts, ACE and BCE. The outcomes were evaluated using CBCT, followed by univariate and multifactorial analyses. Results: A total of 468 patients (age 11.61 ± 4.03 years; male/female 288/180) were analyzed, including 282 in the BCE group (9.41 ± 1.59 years, 175/107) and 186 in the ACE group (14.95 ± 4.31 years, 113/73). Although 5-level assessment revealed no significant difference in clinical success rate (>4 points) between the BCE and ACE groups (53.90% vs. 47.85%, p = 0.20), BCE group showed significantly higher rate of bone bridges formation (73.05% vs. 62.90%, p = 0.02), which can be attributed to variations in orthodontic participation and follow-up time. Independent predictors of graft failure were wide cleft, severe oronasal fistula, no palatal bone wall, and insufficient PCBM filling (p < 0.01). Conclusions: SABG should be performed before canine eruption with more aggressive PCBM filling and oral fistula management.

What is the Success Rate of Repeat Alveolar Bone Graft?

BACKGROUND

Success rates for alveolar bone grafting range from 30 to 96%. There is limited information regarding the success of repeat grafts.

PURPOSE

The purpose of this study was to determine the radiographic success rate of repeat alveolar bone grafts.

STUDY DESIGN

The study designs was a retrospective cohort study of patients who underwent repeat grafting by 1 surgeon over 15 years. To be included, subjects had to have: cleft lip and alveolus and a cone-beam computed tomography (CBCT) scan obtained >6 months after repeat graft. Patients were excluded if CBCT was inadequate.

PREDICTOR VARIABLE

Predictor variables were sex, age at repeat graft, cleft type, presence of an erupted canine, premaxillary osteotomy at time of repeat graft, presence of a visible oronasal fistula, size of bony defect, presence of a bony palatal bridge, and whether the surgeon who performed the repeat graft also performed the initial graft.

MAIN OUTCOME VARIABLE

The outcome variable was graft success determined using CBCT assessment and defined as a score of >3 out of 4 in each domain: vertical bone level, labiopalatal thickness, and piriform symmetry.

COVARIATES

The covariates were time from bone graft to CBCT (months) and age at time of CBCT (years).

ANALYSES

Frequency distributions, relative risk with 95% confidence intervals, medians, and interquartile ranges were calculated. Pearson c2 and Fisher exact tests were performed to determine predictors of outcome. A P < .05 was considered statistically significant.

RESULTS

Fifty subjects (54% male) who had repeat bone grafting to 59 cleft sites were included. Median follow-up time from repeat graft to CBCT was 7.0 months (interquartile range: 5.9 months). The radiographic success rate was 81.4%:91.7% if the same surgeon performed both initial and repeat grafts, but 78.7% if initial graft was completed by another surgeon (P = .43).

CONCLUSION AND RELEVANCE

Despite being a multifactorial issue, extensive and bilateral clefts, the presence of an erupted tooth in the cleft area, a visible oronasal fistula, and concomitant osteotomy of the premaxilla are warning signs of the possibility of failure. Performing repeat alveolar bone grafting by an experienced surgeon appears to increase the chance of success.

Influence of osseous structure characteristics of unilateral alveolar cleft on outcomes of alveolar bone grafting: a retrospective study

BACKGROUND

To enhance the success rate of alveolar bone grafting, it is crucial to identify the factors that may influence the postoperative bone formation. This study aimed to investigate the impact of various osseous structure characteristics of alveolar clefts on the survival ratio of autogenous cancellous bone particle grafts.

METHODS

A retrospective study was conducted on 60 patients who underwent surgery performed by the same surgeon between 2016 and 2022. Two researchers measured and recorded the bone defect volume (DV), postoperative bone formation volume at 1 year, contact area between the graft and the bone surface within the cleft (S), cleft width (CW), osseous occlusion relationships, and presence of a cleft palate and initial bone bridge within the cleft for each patient. Pearson correlation analysis, Spearman's correlation analysis, and multiple linear regression analysis were performed.

RESULTS

The analysis results revealed statistical correlations between DV, CW, ratio of S to DV, cleft palate, initial bone bridge presence, and occlusion relationships with the survival rate. Multiple linear regression analysis showed that initial bone bridge and occlusion relationships affected the graft survival rate.

CONCLUSIONS

Based on the presence of initial bone bridges and occlusions, we can make a rough estimate of the postoperative bone formation outcome in patients. However, the underlying mechanisms by which these two factors influence the bone formation require further investigation. In addition, preoperative orthodontic treatment to improve occlusal relationships may improve the postoperative bone formation outcomes in alveolar bone grafting.

The potential role of cfDNA-related innate immune responses in postoperative bone loss after alveolar bone grafting

The purpose of treating alveolar bone cleft is to restore a normal maxilla structure. Multiple factors have been identified that can affect the success of alveolar bone grafting. However, with consistent treatment modifications, the surgical outcomes have been improved, but alveolar bone loss still exists. Thus, a new aspect should be found to solve this problem. As alveolar bone belongs to the periodontal tissues, the mechanism of the alveolar bone loss after bone grafting in patients with alveolar bone cleft may be similar to the development of alveolar bone loss in periodontitis. Cell-free DNA (cfDNA) has been demonstrated as a key promoter of alveolar bone loss during periodontal inflammation. We hypothesized that cfDNA-related innate immune responses could be a major inducement for postoperative bone loss after alveolar bone grafting. In this perspective, we preliminarily proved the potential association between cfDNA, TLR9 pathway, and alveolar bone grafting operation, and it might verify that surgical trauma could accumulate cfDNA, which can further activate cellular TLR9 signaling.